ABSTRACT
RESUMO A cada dia, cepas bacterianas estão tornando-se resistentes a diversos antibióticos, o que faz necessária a busca de novas substâncias eficazes para o tratamento de doenças. Desta forma, este trabalho reporta o estudo preliminar toxicológico, antibacteriano e fitoquímico do extrato etanólico das folhas de Jatropha mollissima (pinhão-bravo, Euphorbiaceae), coletada no Município de Tauá, Ceará, Nordeste Brasileiro. Inicialmente, realizou-se o teste de toxicidade do extrato contra Artemia salina. Na sequencia, foi realizado o ensaio antibacteriano contra quatro cepas bacterianas Gram-negativas (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Hafnia alvei ATCC 51873, Klebsiella pneumoniae ATCC 13883) e uma cepa Gram-positiva (Enterococcus faecalis ATCC 29212). Finalmente, fez-se a análise fitoquímica preliminar do extrato ativo para detecção das principais classes de metabólitos especiais. Como resultado, o extrato etanólico das folhas de J. mollissima se mostrou tóxico para Artemia salina, pois apresentou CL50 igual a 406,02 μg/mL. Quanto à ação antibacteriana, o extrato se mostrou ativo contra a bactéria Gram-positiva Enterococcus faecalis ATCC 29212, apresentando moderada atividade antibacteriana (halo de inibição igual a 7,03 mm). Evidenciou-se no extrato bioativo a presença de cumarinas, fenóis, taninos, flavonoides (flavonóis e flavanonas), alcaloides e esteroides, ambas as classes reportadas como antimicrobianos. Portanto, esse extrato tem potencial para ser usado na produção de fármacos contra infecções causadas por bactérias Gram-positivas. No entanto, as informações direcionam estudos futuros para o isolamento e identificação dos compostos bioativos, monitorados sob a ação antibacteriana mais expressiva.
ABSTRACT Each day, bacterial strains are becoming more resistant to various antibiotics, which requires the search for new effective substances for the treatment of diseases. Thus, this study reports the toxicological, antibacterial, and phytochemical preliminary study of the ethanolic extracts of Jatropha mollissima (pinhão-bravo, Euphorbiaceae) leaves, collected in Tauá, Ceará, Northeast of Brazil. Initially, we performed the toxicity testing of the extract against Artemia salina. Then, we conducted the antibacterial assay against four Gram-negative bacterial strains (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Hafnia alvei ATCC 51873, Klebsiella pneumoniae ATCC 13883), and one Gram-positive strain (Enterococcus faecalis ATCC 29212). Finally, we carried out the preliminary phytochemical analysis of the active extract to detect the main classes of special metabolites. As a result, the ethanolic extract of J. mollissima leaves was toxic to Artemia salina, because it presented LC50 equal to 406.02 µg/mL. Regarding antibacterial action, the extract was active against the Gram-positive bacteria Enterococcus faecalis ATCC 29212, with moderate antibacterial activity (inhibition zone equal to 7.03 mm). The bioactive extract had the presence of coumarins, phenols, tannins, flavonoids (flavanols and flavonones), alkaloids and steroids, both classes reported as antimicrobials. Therefore, this extract has the potential to be used in the production of drugs against infections caused by Gram-positive bacteria. However, these information require further studies for the isolation and identification of bioactive compounds, monitored under the more expressive antibacterial action.
Subject(s)
Toxicity Tests/methods , Euphorbiaceae/classification , Anti-Bacterial Agents , Artemia/classification , Enterococcus faecalis/classificationABSTRACT
The diurnal ingestive behavior of dairy cows on alfalfa pastures supplemented with corn silage and concentrate was evaluated. Sixteen Holstein dairy cows in mid-lactation were used in a randomized block design. The treatments were partial replacement of corn silage for limited alfalfa grazing time (LGT) or unlimited grazing time (UGT). Rotational alfalfa grazing was used and the amount of concentrate fed was the same in both treatments. Behavioral activities observed were time spent grazing, rumination and idleness, during four days, from 8:00 AM to 7:00 PM. From 2:00 to 5:00 PM grazing was intermittent and short-lasting on UGT, whereas on LGT grazing activity was longer than UGT in the morning and at the end of the afternoon. Restriction in available grazing time clearly influenced the distribution of time spent with grazing, rumination and idleness throughout the day. However, this effect was not observed in the total time spent in these activities...
Avaliou-se o comportamento ingestivo de vacas leiteiras com acesso restrito ou irrestrito a uma pastagem de alfafa suplementada com silagem de milho e concentrado. Utilizaram-se 16 vacas da raça Holandesa, em estádio médio de lactação, em delineamento em blocos ao acaso. Os tratamentos foram: silagem de milho substituída parcialmente por pastejo restrito ou irrestrito de alfafa. As vacas foram manejadas em sistema de pastejo rotacionado e a quantidade de concentrado foi igual em ambos os tratamentos. As atividades comportamentais observadas foram pastejo, ruminação e ócio, das oito às 19 horas, em quatro ocasiões. No pastejo irrestrito, observou-se que, nos horários entre 14 e 17 horas, o pastejo foi intermitente e de curta duração, enquanto no pastejo restrito a atividade de pastejo foi mais prolongada durante a manhã e no final da tarde. A restrição no tempo disponível para pastejo da alfafa influenciou marcadamente a distribuição, no decorrer do dia, do tempo gasto em pastejo, da ruminação e do ócio. Entretanto, não se observou este efeito no tempo total gasto nestas atividades...
Subject(s)
Animals , Female , Cattle , Animal Feed , Animal Nutritional Physiological Phenomena , Lactation , Medicago sativa , Pasture , Zea mays , Temporal Distribution , Time FactorsABSTRACT
O presente estudo foi conduzido com o objetivo de verificar a ocorrência de Salmonella spp. e Staphylococcus coagulase positiva em pescados e crustáceos provenientes da região nordeste no período de fevereiro de 2004 a dezembro de 2005. Das 143 amostras de peixes e crustáceos (camarão congelado e cauda de lagosta), 5 (3,5%) apresentaram-se positivas para Salmonella spp. Enquanto nas amostras de peixe e cauda de lagosta a contagem de Staphylococcus coagulase positiva foi < 1,0 x 102UFC/g estimado, nas amostras de camarão congelado, em duas a contagem foi 1,0 x 101UFC/g estimado e em uma 2,6 x 101UFC/g estimado, as demais <1,0 x 101UFC/g estimado. Com base nos resultados obtidos conclui-se que as amostras analisadas apresentaram baixos níveis de ocorrência de Salmonella spp. e Staphylococcus coagulase positiva e que, mesmo com estes baixos índices, constantemente deve-se buscar uma melhora na qualidade dos produtos da pesca, melhora esta que passa pelo treinamento constante em boas práticas de fabricação, procedimentos padrões de higienização e análise de perigos e pontos críticos de controle do pessoal que trabalha na pesca ou em fazendas de criação de camarão, bem como dos funcionários das indústrias.
The present study was carried out to evaluate the occurrence of Salmonella spp. and coagulase-positive Staphylococcus in fish and crustaceans from the Brazilian Northeast. Five out of the 143 samples (3.5%) were positive for Salmonella spp. While none of the fish and lobster tail samples were positive for coagulase positive Staphylococcus, two shrimp samples presented an estimated count of 1.0 x 101colony forming units per gram (cfu/g), and one presented 2.6 x 101 cfu/g. The results showed a low level of Salmonella and coagulase positive Staphylococcus occurrence. However, even with these low levels of bacterial numbers in fish and crustaceans we should search look for an improvement in their quality. This improvement should be associated to constant training for good manufacturing practice, a standard procedure of hygiene and analysis of hazards and critical control points related to employees that work as fishers or on shrimp farms, as well as those working in the industry as a whole.
Subject(s)
Animals , Salmonella/isolation & purification , Salmonella Infections, Animal/epidemiology , Staphylococcal Infections/epidemiology , Staphylococcus aureus , Crustacea/microbiology , Fishes/microbiology , Brazil/epidemiologyABSTRACT
The antimicrobial resistance of Salmonella Enteritidis strains isolated from clinical and environmental poultry samples in the Southern Brazil during the years of 1999, 2000 and 2001 was evaluated. Among the 79 isolated samples, 64 (81 percent) were resistant to at least one of the antimicrobial agents tested, showing 22 different resistance patterns. Tetracycline showed the highest percentage (64,5 percent) of resistance among the antimicrobial agents used. Resistance to drugs at different levels was found as the following: ampicillin (1.2 percent), kanamycin (1.2 percent), ciprofloxacin (2.5 percent), enrofloxacin (8.8 percent), gentamicin (21.5 percent), streptomycin (20.2 percent), nitrofurantoin (26.6 percent), and nalidixic acid (30.4 percent). None of the S. Enteritidis strains were resistant to chloramphenicol, norfloxacin, and polimycin B. Among the 64 S. Enteritidis strains that showed resistance, 43 (67.2 percent) were resistant to two or more antimicrobial agents. Twenty-one (32.8 percent) strains were resistant to only one of the antimicrobial agents, 14 to tetracycline, three to nalidixic acid, three to nitrofurantoin, and one to gentamycin. These antimicrobial resistance levels suggest a high occurrence of tetracycline resistant S. Enteritidis strains and resistance to two or more antimicrobial agents.
Subject(s)
Birds , Salmonella enteritidis/isolation & purificationABSTRACT
The results show that the milk production activity in the county of Ilhéus, Bahia state, Brazil, lacks of technologies that could improve milk productivity. General information about the farms were obtained through a survey. Thirty-seven (43.5 percent) farms were smaller or equal to 50ha and 65 (76.5 percent) farms produced 50l of milk per day, characterizing these farmers as small producers. In 46 (54.1 percent) farms no information concerning costs, level of production, reproduction efficiency or sanity of the herds were found. In 29 (34.2 percent) farms the information was registered in portable computer database, six (7.1 percent) farms used structured index cards and four (4.7 percent) farms had desktop computers. Forty-one (48.2 percent) farms had roofed and paved milk facilities, three (3.5 percent) farms had not roofed but paved, in 31 (36.5 percent) farms the corrals were not roofed and unpaved, and 10 (11.8 percent) farms had no constructions.
Subject(s)
Animals , Cattle , Animal HusbandryABSTRACT
Aiming to determining the prevalence of tuberculosis and brucellosis in Ilhéus, Bahia, Brazil, 916 cows aged 24 months or above and allocated in 85 farms were tested. The compared cervical intradermic tuberculosis and serological buffered acidified antigen (BAA), slow tube serum agglutination (STSA) and 2-mercapto ethanol (2-ME) tests were used. The prevalence of tuberculosis and brucellosis was 2.8 and 1.9 percent, respectively. The distribution of positive farms (10.6 percent) is in agreement with the notion that these diseases are widespread in the country
Subject(s)
Animals , Cattle , Brucellosis, Bovine , Tuberculosis, BovineABSTRACT
O objetivo deste trabalho foi comparar três procedimentos de semeadura do leite para diagnóstico microbiológico da mastite bovina: "in natura", pós-congelamento de 12 horas a -20ºC e pós-incubaçäo a 37§C por 12 horas. Foram examinados 256 amostras de leite procedentes de 200 vacas com mastite clínica de cinco propriedades leiteiras. Os resultados bacteriológicos após os tratamentos descritos mostraram aumento dos microrganismos isolados. Observou-se aumento significativo do Staphylococcus sp nas amostras congeladas e incubadas, aumento da Klebsiella sp e do Pseudomonas sp apenas no pós-incubaçäo, e reduçäo do Corynebacterium bovis, nos isolamentos pós-incubaçäo. Näo se obervou diferença entre os tratamentos "in natura" e pós-congelamento. Pode-se concluir que a melhor conduta para diagnóstico da mastite seria a associaçäo destes procedimentos para se obter maior taxa de isolamento, permitindo estabelecer o diagnóstico e instituir a conduta terapêutica adequada
Subject(s)
Animals , Female , Cattle , MastitisABSTRACT
Revisäo de literatura sobre os aspectos éticos e jurídicos do tema "Erros Profissionais, à luz da Odontologia Legal"